Pour lentils into a saucepan and cover with water 1 inch higher than lentils, add chicken Bovril and bring to the boil. Cook until soft (10-15 minutes). Add tomato puree and chopped coriander.

Boil potatoes in salted water until tender. Cool and put to one side.

Spray fry light in a small pan and fry onions, garlic and ginger together until soft. Add curry powder and cook for one minute. Add lemon juice and cook for a further minute.

Add this mixture to the lentils and stir. Cut potatoes into bite size pieces and add to the curry. Bring curry back up to a simmer. Check for seasoning. Cut each tomato into 8 and add to curry one minute before serving.